The Sennheiser CX 400 II are black in-ear headphones that provide superior sound quality and have been designed to comfortably fit in an array of ear sizes. These Sennheiser headphones are fitted with neodymium magnets and dynamic stereo to reproduce a high-quality sound that is delivered through the headphone speakers. The Sennheiser headphones offer an integrated audio control system, which makes it easy for the user to adjust their volume control without accessing their device directly. The Sennheiser headphones are compatible with a number of different devices, including iPods, MP3 players, cell phones, and portable gaming devices. The Sennheiser CX 400 II come with a durable cable and cable winder, which keeps the headphones from fraying with extended use. These in-ear headphones from Sennheiser offer a frequency response of 17-22000 Hz and have a sensitivity rating of 113 dB/mW. The Sennheiser headphones are designed to be lightweight and portable, which makes them extremely easy to travel with